Dump bailer for wells



Dec. 6, 1955 G. A. sHlDELl. Erm.

DUMP BAILER FOR WELLS Filed Aug. :25, 1954 IN V EN TORJ` 6. A. Jb/o/e#C. L. [fonc/J I H /f IINIII i JJ, .in! "a*t.............`

vf 5 M Mw a Y ATTO/F/VEY United States Patent l@ef-:Giilice 2,725,940Patented Dec. 6, 1955 DUMP BAILER FOR WELLS Application August 25, 1954,Serial No. 452,098 s claims. (cl. 16a-63) This invention relates toawell tool of the type commonly referred to as a dump bailer which isemployed for depositing in a well various liquid, solid and semisolidmaterials, such as cement, sand and lgravel, chemcals and plasticmaterials for purposes of sealing', plugging, and treating the wellgenerally. Conventional dump bailers employ mechanically operated valveswhich require a bridge or seat, or other solid obstruction in the wellbore to cause the bailer valve or closure to open and discharge itscontents. Y

The present invention has for its principal object the provision of aform of dump bailer which eliminates the need for such actuatingobstructions and which may be opened at any point along a well fordischarge of its contents.

A further object is to provide an improved bailer construction in whichthe discharge opening is closed by a frangible closure member which isadapted to be shattered by an explosive charge set off inside the tool.

A more specific object is to provide a dump bailer having one or moredischarge openings closed by a glass cylinder which is shatterable by anexplosive charge positioned therein in order to open the bailer fordischarging its contents.

Other and more specific objects of this invention will become apparentfrom the following detailed description when read in conjunction withthe accompanying drawing which illustrates a useful embodiment of theinvention.

In the drawing:

Fig. l is an elevational view of the bailer shown in position in a wellcasing;

Figs. 2 and 3, together, constitute a longitudinal, generally sectional,view of the bailer, Fig. 2 illustrating the upper portion and Fig. 3 thelower portion thereof.

Referring to the drawing, the bailer, which is designated generally bythe numeral 5, is secured to a generally conventional rope socket,designated generally by the numeral 6, mounted on the end of a cable 7employed to lower the device into a well casing 8 lining the bore of awell 9.

The bailer comprises a plurality of tubular sections 10--10 connectedtogether end-to-end by any suitable means, such as internal collars 11,to form a hollow container. It will be understood that as many sectionsof pipe and connecting collars may be employed as may be found desirableto provide a container of the desired length. Threadedly secured to thelower end of the lowermost pipe section 10, by means of one of thecollars 11, is a tubular sleeve 12, having an axial bore 13 and providedwith a plurality of elongated, circumferentially spaced slot-s 14-14 cutthrough the wall of the sleeve to form the discharge openings for thebailer. Bore 13 is counter-bored from its lower end to form thecounter-bore 15 and to provide an internal downwardly facing shoulder 16at a point above the upper ends of slots 14. Shoulder 16 serves as anannular seat to receive the upper end of a tubular liner 17 which isconstructed of readily frangible material, preferably glass. All annularL-shaped gasket 18, constructed of any suitable resilient material, ispositioned between the inner end of liner 17 and shoulder 16 and extendsbetween the portion of sleeve 12 which surrounds the upper end of liner17. The lower end of counter-bore 15 is internally threaded at 19 toreceive a closure plug 20 which is screwed into the lower end of thecounter-bore and also serves as an `abutment to hold liner 17 in placewithin the counterbore. When plug 20 is screwed into the end of thecounter-bore, it will thrust the liner tightly against shoulder 16. y AnL-shaped resilient gasket 21, generally like gasket 18, is seatedbetween the lower end of liner 17 and the upper end of plug 20 andextend-s concentrically between the exterior of the lower end of liner17 and the adjacent portion of sleeve 12. The gaskets 18 and 21 serveboth as resilient seals and shock-absorbent protective cushions betweenthe ends of liner 17 and the adjacent portions of the plug and sleeve.This is particularly useful when liner 17 is constructed of glass, whichis a preferred embodiment, and thereby prevents glass-to-rnetal contact,while providing eltective fluidtight seals between the liner and thesleeve. A set screw 22 or other locking device is employed to lock plug20 to sleeve 12 when the plug has been screwed into the sleeve to exertthe desired degree of compression on liner 17.

The uppermost section 10 of the bailer body is provided through the sidethereof near its upper end with an opening 23 through which material tobe delivered into the well by the bailer may be introduced into thebailer. A top closure plug 24 is inserted in the upper end of theuppermost section 10 to close the upper end of the bailer and is adaptedto be connected to rope socket 6. Plug 24, when inserted in the end ofsection 10, may be secured therein in any suitable manner, as by meansof screws 25 and by welding, indicated at 26.

Plug 24 is provided with an axial bore 27 in which is removably insertedan electrode contact assembly 28 of generally conventional form whichforms an electrical connection between an electrical conductor 29, whichis embodied in, and forms a part of, cable 7, and electrical leads 30which extend through the interior of the bailer. Secured to the lowerend of leads 30 is an electricallytired body of explosive, such as awell known explosive cap or fuse 31, which is positioned in the bore ofliner 17. It will be understood that cable 7, with conductor 29 therein,leads to the ground surface where any suitable source of electriccurrent, not shown, may be impressed on the conductor 29 in order totransmit current to cap 31 to explode it.

The above-described device is operated in the following manner: Thebailer is assembled, as shown, with the explosive element in place inthe bore of liner 17. The material to be transported into the well anddischarged therein from the bailer is introduced through window 23 intothe interior of the bailer and the thus loaded device will be loweredinto the well to the point at which the material is to be deposited ordischarged. When that point has been attained, current is appliedthrough conductor 29, electrode assembly 2S and leads 30 to theexplosive element 31 which will thus be set 0E and will shatter liner17, allowing the contents of the bailer to discharge through openingsk14 into the well bore.

The device may be re-used by removing plug 20 and installing a new liner17. The electrode assembly and its connected wires may be withdrawn fromthe interior of plug 24 and a new explosive element 31 connected theretovand re-inserted into the device to prepare it for re-use.

The quantity of explosive required to shatter liner 17 will be variabledepending generally upon the character of the material from which theliner is constructed. As noted, glass is the preferred material for theliner, but the liner may be constructed from rigid, but frangible,plastic material, or from frangible metallic material.

It will be understood that various changes and modifications may be madein the details in the illustrative embodiment, within the scope of theappended claims, but without departing from the spirit of the invention.What we claim and desire to secure by Letters Patent 1. A dump bailerfor wells, comprising, a tubular body, a closure for its upper endincluding means for attaching the body to a lowering cable, a illeropening in the wall of the body adjacent said closure, a tubular sleevecoaxially connected to the lower end of the body, a removable plugclosing the lower end of the sleeve, a downwardly facing annularshoulder in the bore of the sleeve axially spaced from the plug, saidsleeve having a discharge passage through the wall thereof between saidshoulder and said plug, a tubular frangible liner coaxially positionedin the bore of said sleeve opposite said passage and having one endabutting said shoulder and the other end abutting said plug, annularresilient seal means disposed to form uid-tight seals between the linerand the wall of said sleeve at points above and below said passagewhereby to close off said passage, an electrically red explosive chargepositioned in the bore of the liner, and means carried by the cable fortiring said charge whereby to shatter said liner and open said passage.

2. A dump bailer as dened by clairn 1, wherein said liner is constructedof glass.

3. A dump bailer as dened by claim 1, wherein said seal means includeportions positioned in axially compressible relation between theopposite ends of said liner and said shoulder and plug respectively.

4. A dump bailer as dened by claim 1, wherein said closure plug isthreadedly inserted in the lower end of the sleeve whereby to adjustablyurge said liner toward said shoulder.

5. A dump bailer for wells, comprising, a tubular body, a closure forthe upper end of said body including means for attaching the body to alowering cable having electric current carrying leads incorporatedtherein, a filler opening in the wall of the body adjacent the closure,a tubular sleeve coaxially connected to the lower end of the body, athreaded closure plug adjustably extendible into the lower end of saidsleeve, a downwardly facing annular shoulder in the bore of said sleevevertically spaced from the inner end of the plug, a plurality ofangularly spaced openings through the wall of said sleeve between saidshoulder and said plug, a tubular glass liner coaxially mounted in thebore of said sleeve having one end urged toward said shoulder by inwardmovement of said plug, annular resilient sealing gaskets between theends of Said liner and the respective abutting surfaces of said shoulderand said plug, an electrically fired explosive charge positioned in thebore of said liner, and electrical conductors connecting said charge tosaid current carrying leads.

References Cited in the le of this patent UNTT ED STATES PATENTSRe.21,356 Pitzer Feb. 13, 194() 1,592,104 Hallvarson July 13, 19262,640,548 Baker lune 2, 1953

